CVE-2026-98636

high

Description

In the Linux kernel, the following vulnerability has been resolved: squashfs: Add dictionary size range check to prevent shift-out-of-bounds When an abnormal SquashFS image (COMP_OPTS flag is 1 but dictionary size is 0) is mounted, and performs shift operations using dictionarysize, the shift exponent is -1, causing a shift-out-of-bounds. Detail as below: squashfs_comp_opts(msblk, buffer, length) squashfs_xz_comp_opts() if (comp_opts) n = ffs(opts->dict_size) - 1;<----opts->dict_size=0, n=-1 if (opts->dict_size != (1 << n) && opts->dict_size != (1 << n) + (1 << (n + 1))) <----shift-out-of-bounds Fix it by adding a dictionary size range check before the shift operation.

References

https://git.kernel.org/stable/c/e1ca4e3a380ef3e8f46ce006f1146392e3f32c98

https://git.kernel.org/stable/c/c68e0068a236f9a7dfc19720bdf11e5d80a85089

https://git.kernel.org/stable/c/b02948a23455f8190a53887b2d2c13ae1d360cea

https://git.kernel.org/stable/c/9d9c5c218ea356a1d88765214ad2919605280ab1

https://git.kernel.org/stable/c/88c673a0bd233df44ca0020da82f4fd3876de27a

https://git.kernel.org/stable/c/7a1c293e7aa17f1afaee0684e0e931fe23a5a6b1

https://git.kernel.org/stable/c/1f7745fb3580152ca902ef181b605f33cabfb1d0

https://git.kernel.org/stable/c/0cb85377daaefb4ce5ce72975f2deb27ee0e0cad

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-103550

Details

Source: Mitre, NVD

Published: 2026-10-18

Updated: 2026-10-19

Risk Information

CVSS v2

Base Score: 2.1

Vector: CVSS2#AV:L/AC:L/Au:N/C:N/I:N/A:P

Severity: Low

CVSS v3

Base Score: 7.1

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

Severity: High

EPSS

EPSS: 0.00176